Former United striker Berbatov returns to Old Trafford on Saturday for the first time since he was offloaded to Fulham for £5m last summer after being frozen out by Ferguson.

Berbatov was perceived as an indulgent purchase by the Scot - a player of undoubted skill and guile, but one whose languid style was ultimately not suited to the club's high-octane play.

But, on the eve of the 31-year-old's return to United, Ferguson defended his decision to buy the Bulgarian and was adamant he justified his huge fee, despite his ultimately short spell at the club.

"I don't think Dimitar was a failure here," he said. "I think he did a great job here.

"The problem is, I had choices and at his age it's not easy to be part of those choices when he's not playing. He wanted regular first-team football and we gave him the opportunity to go to Fulham.

"At his age it was the right thing to do.

"I don't think it's a big step down for Dimitar. It's a step down leaving Manchester United anyway, in my mind, but it's not such a big step down for him.

"He's not given up in terms of his ambition, because he's gone to a club that's quite ambitious. The problem for him here was the way we wanted to play and the selections we had.

"The hardest thing was when we had Carlos Tevez here also. That affected both of them, I think.

"But when you've got choices, you hope you make the right ones. Some people like to see players run through brick walls all the time.

"Dimitar isn't that type of player. But he's a very talented boy who had a decent goalscoring record here. He's done pretty well at Fulham and I think he's their best player.

"Fulham have grown over the last few years. There are very few clubs with full houses every week but Fulham are one of them. They've progressed a lot.

"Reaching the UEFA Cup Final has helped them obviously and they've had healthy positions in the league for the last few years."

Despite being marginalised during his final two seasons at United, Berbatov was joint top scorer in the Premier League in 2010-11 campaign, along with Carlos Tevez, with 20 goals.

That included a five-goal haul in a 7-1 win over Blackburn at Old Trafford, as well as hat-tricks against Liverpool and Birmingham, as United won the title by nine points from City.

Christopher Lee

Stroll on: Berbatov is a regular at Fulham

But Berbatov's United career was effectively over the moment Ferguson chose not to include him in the United squad for the Champions League final against Barcelona at Wembley that season.

Michael Owen made the bench ahead of Berbatov, who was so crushed by his omission he stayed in the dressing-room throughout the final, which United lost 3-1.

"That was very difficult," said Ferguson of the decision to omit Berbatov.

"I looked at the situation in terms of if we needed a goal in the latter part of the match and I felt maybe Michael Owen would be a better one.

"That was it. Straightforward. It was a terrible decision to make. He didn't take it well, which you expect anyway, because everybody wants to play in a cup final.

"I can't quite understand why UEFA don't allow you to have 11 subs on the bench in a European Cup Final.

"On the long road to getting to the final in European football, quite a few players contribute in the group stage and the last 16, eight and four, so you're using quite a few players."

Berbatov became an outcast at United last season, making just five starts in the Premier League, as he became an increasingly peripheral figure at the club.

But at Fulham he has the full trust and confidence of boss Martin Jol, something he was never able to achieve with Ferguson.

Despite the acrimonious way in which his United career ended - Berbatov said he lost respect for Ferguson over the way he was treated - the Old Trafford boss expects him to receive a warm welcome today.

"We've experience of former players coming back and doing well," said Ferguson. "But that doesn't stop supporters recognising the contributions they made.

"I think Dimitar and Kieran Richardson, if he plays, will get the welcome they normally get from our fans for former players.

"We've had former players score against us a few times. Paul Ince did it at Liverpool, but I don't think you should tie yourself in knots about it.

"We're not the only club who can suffer from that, of course. Robin Van Persie scored against Arsenal this season. It's a fact of life."

* FERGUSON said he expects Rio Ferdinand, out of contract at the end of the season, to sign a one-year extension.